Improvement in paddle-wheels



ELIJAH PRATT, OF NEW YORK, ASSIGNOR TO HIMSELF, DAVID M DELL, AND ALFRED MUNDELL, OFBROOKLYN, NEW YORK.

Letters Patent No. 113,561, dated April 11, 1871;/

IMPROVEMENT Iny PAoDLE-wHEELS.

The Schedule referred to iii these Lettere Patent and making part of the name.

To all whom 'it may concern:

Be it known that I, ELIJAH PRATT, of New York, in the county of New York and State of New York, have invented some new and useful Improvemelts v in the Paddle-Wheels of Steamboats; and I do hereby declare that the following is a full and exact description thereof, reference beinghad to the accompanying drawing making part of this specification?- Figure l beinga side elevation of a-steamboat pad- {lle-wheel constructed with my improvements;

Figure 2, a vertical section of the same in a plane indicated by the line :v x, fig. l;

Figure 3, a view of one of the grooved cam-plates, by which the Amovements of the paddles are produced;

Figures "4 and5, views, respectively, of the switches or pivoter] switch-blocks, by which the passage from onecam-groove to another is controlled.

'Like letters designate corresponding parts in all of the figures.A

,The object of my invention `is to produce a more complete and effective' movement of the paddles or floats of the paddle-wheels of that kind in which the paddles are drawn nearer to the center of the wheel. in rising from the water, and are again moved outward before descending into the water; and

The nature of inyinvention consists- First, in the device by which the outward and inward movements of the paddles are e'eeted, the, same when the paddle-wheels are moving backward as when turning forward; and

Second, in the device by which the outward and inward movements of the paddles are effected, by cams near the shaft of the wheel, and as small inextent as desired.

LetA represent the Wheel-house around the wheel, and

B, the paddle-wlscelof `a'. steamboat. l

The frame-work of the wheel may be made as usual, except that the radial arms c c thereof have longitudinal slots formed therein, in which the paddles or oats D D may slide inward and outward to the extent desired; or any equivalent guide arrangement for the paddles may be adopted.

And since the paddles do not contribute to the strength of the framefwork of the wheel, cross-bars E E may extend across the wheel and connect the ends of the radial arms, being, preferably, made thin and sharp-edged, so as to go through the water with the least resistance. lhey also serve to protect thepaddles from obstructions, and from clogging with sea weeds, Ste.

In order to avoid the necessity of employing cams or guides of the full diameter of the sweep of the paddles, and to bring them within l practicablelimits, .each paddle is connected, by suitable connecting rods,

with a rod or roller, F, nearer the shaft of the wheel.

These rods F F extend across the width of the wheel and through separate slots of the radial arms thereof, and into the grooves of cam-plates G G, which are respectively secured tothe opposite inner surfaces of the 'wheel-house.

' Theinner slots of the wheel-arms are of sudicieut length to allow as much outward and inward motion of the rods F F as is to be given to the paddles.

The ends of the rods F F have friction-'rollers ,ff thereon to run in the camlgrooves with as little i'ric'f tion as possible ;u and similar friction-rollers or sleeves may surround the rods where they-play in the slots of the wheel-arms.

The cam-plates G G are constructed with two pairsL of cam-grooves, H H and J J, iheouter grooves H H being such as to hold thefrods F F, and consequently 'the paddles D D, to their outermost limit; and the inner grooves J J such as to hold the saine to their innermost limits.

The'rods F F descend in the outer grooves H H, respectively, whether the wheel is turning forward or backward, thereby causingtbep'addles to dip as far as required intothe water when descending and the rods ascend in the inner grooves J J, respectively, whichever way the wheel turns, so as to draw the paddlestoward the center of the wheel in ascending to avoid the back-lift and resistance of the water as the paddles rise out ot' the same, and to diminish 'the resistant leverage' of their weight in rising aswell asto increase the leverage of their weight in descend ing.

In order to change the passage oi' the rods F F from the outer to the inner grooves of the cam-plate in ascending, and from theinner to the outer grooves before descending, there is a connectingpassage or passages between the Youter and inner grooves, both at the bottom and top; and there are two swinging switch-blocks, K K, so located in the bottom passages as to swing and canse the rods to ascend into the inner grooves whether moving in one direction or the other, and to swing over and cover the passage ou the7 other side and prevent the descent oi' the rods again into the outer groove.

Another swinging switch-block, L, is located in the upper connecting-passage, so as to direct the rods from-the inner to the outer` grooves, in either direction of their movement.

1. The guide-cam plates G G, provided with theV outer cam-grooves B' H and inner cam-grooves J J,

and with connecting-passages controlled bythe switohcam guide-rods F F, double-slotted wheel-arms c c, blocks K K L or their equivalents', substantially as and cam-plates G G, constructed and arranged suband for the purpose herein specified. y stnntally as and for the purpose herein specilied.

2. The guide-rods F F, moving in inner slots of ELIJAH PRATT. the wheel-arms, in combination with the calm-plates G G and paddles D D, substantially as and forA the Witnesses: purpose herein specified. J; S. BROWN,

3. The combination of the sliding-paddles D D, D. J. BROWN. 

